The Dediyagala Reserve offers a unique opportunity to observe some of Sri Lanka's endemic bird species such as the Sri Lanka Spurfowl, Sri Lanka Junglefowl, and Malabar Trogon. Among the mammals, the black monkey and slender loris hold a special place. Visitors can also spot several endemic butterfly species, including the striking Blue Mormon.
The reserve is home to unique species of amphibians and reptiles, along with endemic freshwater fish such as Bulath Hapaya, Vilpita Dandiya, and Patirana Sala. This makes Dediyagala a haven for wildlife enthusiasts and nature lovers.